Zach Rodgers1, Varsha Jain1, Michael Langham2, Felix W. Wehrli2
1Bioengineering, University of Pennsylvania, Philadelphia, PA, United States; 2Radiology, University of Pennsylvania, Philadelphia, PA, United States
CMRO2 was quantified during an apnea paradigm using an interleaved, multi-slice GRE pulse sequence. A temporal resolution of five seconds was achieved through a combination of projection velocity quantification and keyhole phase difference mapping to derive venous oxygen saturation (SvO2). CMRO2 was observed to remain constant during apnea due to a concomitant increase in flow and SvO2, but drop immediately post-apnea due to a delay in the equilibration of SvO2 relative to flow. The technique described can be applied to study cerebral metabolism and neurovascular coupling during dynamic physiologic challenges.